1 ;;;; This file contains some parameterizations of various VM
2 ;;;; attributes for the x86. This file is separate from other stuff so
3 ;;;; that it can be compiled and loaded earlier.
5 ;;;; This software is part of the SBCL system. See the README file for
8 ;;;; This software is derived from the CMU CL system, which was
9 ;;;; written at Carnegie Mellon University and released into the
10 ;;;; public domain. The software is in the public domain and is
11 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
12 ;;;; files for more information.
16 ;;; ### Note: we simultaneously use ``word'' to mean a 32 bit quantity
17 ;;; and a 16 bit quantity depending on context. This is because Intel
18 ;;; insists on calling 16 bit things words and 32 bit things
19 ;;; double-words (or dwords). Therefore, in the instruction definition
20 ;;; and register specs, we use the Intel convention. But whenever we
21 ;;; are talking about stuff the rest of the lisp system might be
22 ;;; interested in, we use ``word'' to mean the size of a descriptor
23 ;;; object, which is 32 bits.
25 ;;;; machine architecture parameters
27 ;;; the number of bits per word, where a word holds one lisp descriptor
28 (def!constant n-word-bits 32)
30 ;;; the natural width of a machine word (as seen in e.g. register width,
32 (def!constant n-machine-word-bits 32)
34 ;;; the number of bits per byte, where a byte is the smallest
35 ;;; addressable object
36 (def!constant n-byte-bits 8)
38 (def!constant float-sign-shift 31)
40 ;;; comment from CMU CL:
41 ;;; These values were taken from the alpha code. The values for
42 ;;; bias and exponent min/max are not the same as shown in the 486 book.
43 ;;; They may be correct for how Python uses them.
44 (def!constant single-float-bias 126) ; Intel says 127.
45 (defconstant-eqx single-float-exponent-byte (byte 8 23) #'equalp)
46 (defconstant-eqx single-float-significand-byte (byte 23 0) #'equalp)
47 ;;; comment from CMU CL:
48 ;;; The 486 book shows the exponent range -126 to +127. The Lisp
49 ;;; code that uses these values seems to want already biased numbers.
50 (def!constant single-float-normal-exponent-min 1)
51 (def!constant single-float-normal-exponent-max 254)
52 (def!constant single-float-hidden-bit (ash 1 23))
53 (def!constant single-float-trapping-nan-bit (ash 1 22))
55 (def!constant double-float-bias 1022)
56 (defconstant-eqx double-float-exponent-byte (byte 11 20) #'equalp)
57 (defconstant-eqx double-float-significand-byte (byte 20 0) #'equalp)
58 (def!constant double-float-normal-exponent-min 1)
59 (def!constant double-float-normal-exponent-max #x7FE)
60 (def!constant double-float-hidden-bit (ash 1 20))
61 (def!constant double-float-trapping-nan-bit (ash 1 19))
63 (def!constant long-float-bias 16382)
64 (defconstant-eqx long-float-exponent-byte (byte 15 0) #'equalp)
65 (defconstant-eqx long-float-significand-byte (byte 31 0) #'equalp)
66 (def!constant long-float-normal-exponent-min 1)
67 (def!constant long-float-normal-exponent-max #x7FFE)
68 (def!constant long-float-hidden-bit (ash 1 31)) ; actually not hidden
69 (def!constant long-float-trapping-nan-bit (ash 1 30))
71 (def!constant single-float-digits
72 (+ (byte-size single-float-significand-byte) 1))
74 (def!constant double-float-digits
75 (+ (byte-size double-float-significand-byte) n-word-bits 1))
77 (def!constant long-float-digits
78 (+ (byte-size long-float-significand-byte) n-word-bits 1))
80 ;;; pfw -- from i486 microprocessor programmer's reference manual
81 (def!constant float-invalid-trap-bit (ash 1 0))
82 (def!constant float-denormal-trap-bit (ash 1 1))
83 (def!constant float-divide-by-zero-trap-bit (ash 1 2))
84 (def!constant float-overflow-trap-bit (ash 1 3))
85 (def!constant float-underflow-trap-bit (ash 1 4))
86 (def!constant float-inexact-trap-bit (ash 1 5))
88 (def!constant float-round-to-nearest 0)
89 (def!constant float-round-to-negative 1)
90 (def!constant float-round-to-positive 2)
91 (def!constant float-round-to-zero 3)
93 (def!constant float-precision-24-bit 0)
94 (def!constant float-precision-53-bit 2)
95 (def!constant float-precision-64-bit 3)
97 (defconstant-eqx float-rounding-mode (byte 2 10) #'equalp)
98 (defconstant-eqx float-sticky-bits (byte 6 16) #'equalp)
99 (defconstant-eqx float-traps-byte (byte 6 0) #'equalp)
100 (defconstant-eqx float-exceptions-byte (byte 6 16) #'equalp)
101 (defconstant-eqx float-precision-control (byte 2 8) #'equalp)
102 (def!constant float-fast-bit 0) ; no fast mode on x86
104 ;;;; description of the target address space
106 ;;; where to put the different spaces
108 ;;; Note: Mostly these values are black magic, inherited from CMU CL
109 ;;; without any documentation. However, there were a few explanatory
110 ;;; comments in the CMU CL sources:
112 ;;; ** The space 0x08000000-0x10000000 is "C program and memory allocation".
113 ;;; ** The space 0x40000000-0x48000000 is reserved for shared libs.
114 ;;; ** The space >0xE0000000 is "C stack - Alien stack".
116 ;;; ** The space 0x0E000000-0x10000000 is "Foreign segment".
117 ;;; ** The space 0x20000000-0x30000000 is reserved for shared libs.
118 ;;; And there have been some changes since the fork from CMU CL:
119 ;;; * The OpenBSD port is new since the fork. We started with
120 ;;; the FreeBSD address map, which actually worked until the
121 ;;; Alpha port patches, for reasons which in retrospect are rather
122 ;;; mysterious. After the Alpha port patches were added, the
123 ;;; OpenBSD port suffered memory corruption problems. While
124 ;;; debugging those, it was discovered that src/runtime/trymap
125 ;;; failed for the control stack region #x40000000-#x47fff000.
126 ;;; After the control stack was moved upward out of this region
127 ;;; (stealing some bytes from dynamic space) the problems went
129 ;;; * The FreeBSD STATIC-SPACE-START value was bumped up from
130 ;;; #x28000000 to #x30000000 when FreeBSD ld.so dynamic linking
131 ;;; support was added for FreeBSD ca. 20000910. This was to keep from
132 ;;; stomping on an address range that the dynamic libraries want to
133 ;;; use. (They want to use this address range even if we try to
134 ;;; reserve it with a call to validate() as the first operation in
136 ;;; * For NetBSD 2.0, the following ranges are used by normal
137 ;;; executables and mmap:
138 ;;; ** Executables are (by default) loaded at 0x08048000.
139 ;;; ** The break for the sbcl runtime seems to end around 0x08400000
140 ;;; We set read only space around 0x20000000, static
141 ;;; space around 0x30000000, all ending below 0x37fff000
142 ;;; ** ld.so and other mmap'ed stuff like shared libs start around
144 ;;; We set dynamic space between 0x60000000 and 0x98000000
145 ;;; ** Bottom of the stack is typically not below 0xb0000000
146 ;;; FYI, this can be looked at with the "pmap" program, and if you
147 ;;; set the top-down mmap allocation option in the kernel (not yet
148 ;;; the default), all bets are totally off!
153 (def!constant read-only-space-start #x02000000)
154 (def!constant read-only-space-end #x047ff000)
156 (def!constant static-space-start #x05000000)
157 (def!constant static-space-end #x07fff000)
159 (def!constant dynamic-space-start #x09000000)
160 (def!constant dynamic-space-end #x29000000)
162 (def!constant linkage-table-space-start #x30000000)
163 (def!constant linkage-table-space-end #x40000000))
167 (def!constant read-only-space-start #x01000000)
168 (def!constant read-only-space-end #x037ff000)
170 (def!constant static-space-start #x05000000)
171 (def!constant static-space-end #x07fff000)
173 (def!constant dynamic-space-start #x09000000)
174 (def!constant dynamic-space-end #x29000000)
176 (def!constant linkage-table-space-start #x70000000)
177 (def!constant linkage-table-space-end #x7ffff000))
181 (def!constant read-only-space-start #x20000000)
182 (def!constant read-only-space-end #x2ffff000)
184 (def!constant static-space-start #x40000000)
185 (def!constant static-space-end #x42fff000)
187 (def!constant dynamic-space-start #x48000000)
188 (def!constant dynamic-space-end #xA0000000)
190 (def!constant linkage-table-space-start #xA2000000)
191 (def!constant linkage-table-space-end #xA3000000))
195 (def!constant read-only-space-start #x10000000)
196 (def!constant read-only-space-end #x1ffff000)
198 (def!constant static-space-start #x30000000)
199 (def!constant static-space-end #x37fff000)
201 (def!constant dynamic-space-start #x48000000)
202 (def!constant dynamic-space-end #x88000000)
204 ;; In CMUCL: 0xB0000000->0xB1000000
205 (def!constant linkage-table-space-start #x90000000)
206 (def!constant linkage-table-space-end #x91000000))
210 (def!constant read-only-space-start #x40000000)
211 (def!constant read-only-space-end #x47fff000)
213 (def!constant static-space-start #x50000000)
214 (def!constant static-space-end #x5ffff000)
216 (def!constant dynamic-space-start #x80000000)
217 (def!constant dynamic-space-end #xA0000000)
219 ;; In CMUCL: 0xB0000000->0xB1000000
220 (def!constant linkage-table-space-start #xA0000000)
221 (def!constant linkage-table-space-end #xA1000000))
225 (def!constant read-only-space-start #x20000000)
226 (def!constant read-only-space-end #x2ffff000)
228 (def!constant static-space-start #x30000000)
229 (def!constant static-space-end #x37fff000)
231 (def!constant dynamic-space-start #x60000000)
232 (def!constant dynamic-space-end #x98000000)
234 ;; In CMUCL: 0xB0000000->0xB1000000
235 (def!constant linkage-table-space-start #xA0000000)
236 (def!constant linkage-table-space-end #xA1000000))
241 (def!constant read-only-space-start #x04000000)
242 (def!constant read-only-space-end #x07ff8000)
244 (def!constant static-space-start #x08000000)
245 (def!constant static-space-end #x097fff00)
247 (def!constant dynamic-space-start #x10000000)
248 (def!constant dynamic-space-end #x6ffff000)
250 (def!constant linkage-table-space-start #x0a000000)
251 (def!constant linkage-table-space-end #x0b000000))
253 ;;; Size of one linkage-table entry in bytes.
254 (def!constant linkage-table-entry-size 8)
256 ;;; Given that NIL is the first thing allocated in static space, we
257 ;;; know its value at compile time:
258 (def!constant nil-value (+ static-space-start #xb))
260 ;;;; other miscellaneous constants
262 (defenum (:suffix -trap :start 8)
271 ;;; FIXME: It'd be nice to replace all the DEFENUMs with something like
272 ;;; (WITH-DEF-ENUM (:START 8)
273 ;;; (DEF-ENUM HALT-TRAP)
274 ;;; (DEF-ENUM PENDING-INTERRUPT-TRAP)
276 ;;; for the benefit of anyone doing a lexical search for definitions
277 ;;; of these symbols.
279 (defenum (:prefix object-not- :suffix -trap :start 24)
283 (defenum (:prefix trace-table-)
291 ;;; These symbols are loaded into static space directly after NIL so
292 ;;; that the system can compute their address by adding a constant
295 ;;; The fdefn objects for the static functions are loaded into static
296 ;;; space directly after the static symbols. That way, the raw-addr
297 ;;; can be loaded directly out of them by indirecting relative to NIL.
299 ;;; pfw X86 doesn't have enough registers to keep these things there.
300 ;;; Note these spaces grow from low to high addresses.
301 (defvar *allocation-pointer*)
302 (defvar *binding-stack-pointer*)
304 (defparameter *static-symbols*
306 *common-static-symbols*
307 *c-callable-static-symbols*
310 ;; interrupt handling
312 #!+sb-thread *stop-for-gc-pending*
313 #!+sb-thread *free-tls-index*
314 #!+sb-thread *tls-index-lock*
317 *binding-stack-pointer*
319 ;; the floating point constants
324 ;; The following are all long-floats.
334 *restart-lisp-function*
336 ;; Needed for callbacks to work across saving cores. see
337 ;; ALIEN-CALLBACK-ASSEMBLER-WRAPPER in c-call.lisp for gory
339 sb!alien::*enter-alien-callback*
341 ;; see comments in ../x86-64/parms.lisp
342 sb!pcl::..slot-unbound..)))
344 (defparameter *static-funs*
355 sb!kernel:two-arg-and
356 sb!kernel:two-arg-ior
357 sb!kernel:two-arg-xor
358 sb!kernel:two-arg-gcd
359 sb!kernel:two-arg-lcm))
361 ;;;; stuff added by jrd
363 ;;; FIXME: Is this used? Delete it or document it.
364 ;;; cf the sparc PARMS.LISP
365 (defparameter *assembly-unit-length* 8)